The present disclosure relates to devices for pulling and harvesting root crops, such as sugar beets. Sugar beets are one type of root vegetable that is cultivated and harvested in large quantities. Sugar beets and other similar root vegetables can be harvested using a harvester having sets of puller wheels that are attached to a frame that is drawn along the ground behind a tractor, the puller wheels gripping and pulling each sugar beet from the ground. In this type of harvester, each pair of puller wheels are aligned with each row of beets, and the wheels are canted at an angle relative to each other and relative to the direction of motion of the tractor. This angle of the wheels relative to each other and relative to the direction of the pulling vehicle causes the wheels to dig into the ground and rotate as they are drawn along causing the wheels to grip the sugar beets or other root crop at a pinch point (the point of minimum clearance between opposing puller wheels) as the device rolls along. This action of the puller wheels grabs and pulls the root crops out of the ground one-by-one. Paddle wheels can be provided to rotate above and between each pair of puller wheels to knock the beets from between the wheels and place them on an output mechanism, such as a conveyor belt.
It can be desirable to modify the location of the pinch point to ensure that beets reach the conveyor belt or other output mechanism, and are not prematurely released. The pivot point for each puller wheel assembly is located upon the frame being drawn by the tractor. Traditionally, the longitudinal location of the pinch point (i.e. the location of the pinch point relative to the direction of motion of the harvester) can be adjusted by adding spacers to rotate each individual puller wheel assembly down relative to the frame that carries the puller wheels. However, in this approach, each wheel assembly must be individually adjusted and disassembly may be required. Additionally, in this approach, the location of the pinch point relative to the paddle wheel is changed because the position of the paddle wheel is not affected by the spacers.
The present application is directed to one or more of the above issues.